Antibiotic MYC 8003 and process for producing same

ABSTRACT

An antibiotic being a yellow, salt-forming weak acid, and its non-toxic, pharmaceutically acceptable salts produced by a microorganism called Streptomyces ramocissimus, a sample of which is deposited in the collection of &#39;&#39;&#39;&#39;Centraal Bureau voor Schimmelcultures&#39;&#39;&#39;&#39; at Baarn, The Netherlands, under No. CBS 190.69, or mutants thereof, which antibiotic possesses growthpromoting properties and is especially useful to be added to animal feed although the antibiotic may also be used for therapeutic purposes.

United States Patent [191 Vos et al.

[ Dec. 16, 1975 ANTIBIOTIC MYC 8003 AND PROCESS FOR PRODUCING SAME [75] Inventors: Comelis Vos, Pijnacker; Jacobus Den Admirant, Delft, both of Netherlands [73] Assignee: Gist-Brocades N.V., Delft,

Netherlands [22] Filed: Mar. 26, 1973 [21] Appl. No.: 344,610

Related US. Application Data [63] Continuation-impart of Ser. No. 170,516, Aug. l0,

I971, abandoned.

[30] Foreign Application Priority Data Aug. 14, I970 United Kingdom 39367/70 [52] US. Cl. 424/122 [51] Int. Cl A61k 21/00 [58] 'Field of Search 424/122; 195/80 R [56] References Cited OTHER PUBLICATIONS Chemical Abstracts 79zl30ls (1974).

Primary Examiner-Jerome D. Goldberg Attorney, Agent, or Firm-Hammond & Littell 3 Claims, 6 Drawing Figures U.S. Patent Dec. 16, 1975 Sheet 1 of2 3,927,211

HQOH-H O MEOH-O N NOOH 1n. MeOH-O.SN HCl o. l I I I I V 4000 3000 2000 1000 500 FIGS US. Patent Dec. 16,1975 Sheet2of2 3,927,211

PPM H64 FRONT O. I 3 O 2 0 I START ANTIBIOTIC MYC 8003 AND PROCESS FOR PRODUCING SAME PRIOR APPLICATION This application is a continuation-in part of copending, commonly assigned application Ser. No. 170,516 filed Aug. 10, 1971, now abandoned.

OBJECTS OF. THE INVENTION THE INVENTION The new antibiotic, referred to as MYC 8003 (now called mocimycin), is of special value for its growthpromoting properties when administered to live-stock. It also has a considerable activity in vitro against organisms of the Mycoplasma genus (pleuropneumonia like organisms) and is active against some bacteria, for example Actinobacillus equuli. It is obtained from culture media of the microorganism which is characterized in detail hereafter belonging to the genus Streptomyces. The microorganism producing the antibiotic has not been described hitherto, and a' specimen of it has been deposited in the collection of Centraal Bureau voor Schimmelcultures at Baarn, The Netherlands, where it has been given the number CBS 190.69 and is available to the public.

The species of Streptomyces described herein and identified as Streptomyces MYC 8003 includes all strains of Streptomyces which produce antibiotic MYC 8003 and which cannot be definitely differentiated from the strain CBS 190.69 and its subcultures, including mutants and variants. By the term mutants as used herein there is intended mutants produced from the described organism by various means such as chemical mutagenic agents, ultra-violet radiation, X-radiation, phage exposure and the like. The properties of antibiotic MYC 8003 are described herein and after these properties are known it is easy to differentiate the strains producing antibiotic MY C 8003 from others. The novel microorganism has been called Streptomyces ramocissimus. Y

The antibiotic of the present invention is a weak acid and forms non-toxic, pharmaceutically acceptable salts, which are antibiotically active, such as alkali metals, e.g. sodium, and potassium, ammonium and amine salts. It has the following physico chemical properties Solubility:

The solubility of the antibiotic'is good in chloroform, methyl isobutyl ketone, butyl acetate, ethyl acetate, acetone, methanol and alkaline solutions. The solubility is poor in carbon tetrachloride and benzene, and the 2 antibiotic is insoluble in diethyl ether, petroleum ether, water and acid solutions. Stability:

Tests have shown that, over periods of about 4 hours at ambient temperature, the antibiotic when dissolved in 50 aqueous methanol is stable within a pH range of 3 to 12. The solid antibiotic stored at 25C and 37C at low relative humidities shows no loss in activity for at least 5 months. It is stable for 3 months at 25C and relative humidity and for-2 months at 37C and 100 relative humidity.

Reactions on possible function groups:

TABLE I Reagent Result Conc. Sulfuric acid dissolution and formation of a red colour Aromate test (AlCl chloro- I slightly positive form) Fehlings reaction (aldehydes) negative Tollens' reaction (aldehydes) negative Molisch reaction (saccharides) negative Anthron reaction (saccharides) negative Biuret reaction (proteins) negative Folin L reaction (proteins negative amino acids) Pauly reaction (amino acids phenols) FeCl reaction (enols phenols) dark brown colour dark red colour and turbidity positive precipitation due to acid formation Bromination in CHCl Bromination in water Optical rotation:

[04],, 60 (1 methanolic solution) Melting point:

The antibiotic does not have a sharp melting point or melting range. At C, a gas production takes place, while the antibiotic softens. At about 152C, gas is again produced. At 164 174C, the antibiotic is molten.

Ultra-violet Spectrum:

The antibiotic shows a specific spectrum with maxima at a wave-length of 233, 276, 286 and 327 nm. At different pH values, different spectra are obtairled as shown in FIG. 1. In FIG. 1, the solid line stands for a 13 mg/l solution of the antibiotic in a mixture of equal amounts of methanol and water and the broken line stands for a similar solution, except that the water is replaced by 0.5N sodium hydroxide, while the dotted line stands for a similar solution except that the .water is replaced by 0.5N hydrochloric acid.

Thin-layer chromatography of the antibiotic reveals the presence of three compounds. By two-dimensional chromatography where the second elution was carried out at least 12 hours after the first, it was found that these three components are in equilibrium with each other. The results obtained with three solvent systems are given in FIGS. 2, 5 and 6.

The first chhromatogram (FIG. 2) has been made on silica gel with the solvent mixture consisting of acetone, ethyl acetate and water 12:8: 1 The dotted line indicates the start, and the spots 1, 2 and 3 indicate the components.

The second chromatogram (FIG. 5) is obtained with the solvent system methyl isobutyl ketone, acetone and water (50:45:5) and the third (FIG. 6) with benzene, ethanol and 33 ammonia (6514019). For the chromatograms of FIGS. 5 and'6, Kieselgel F 254 plates (Merck) were used. The spots are detected by using UV light of a short wave length giving dark spots on a 3 fluorescing back ground. The R values obtained are: first component (chief component) 0.5, 0.29 and 0.10, second component: 0.7, 0.44 and 0.20 and third component: 0.3, 0.16 and 0.76, respectively. Infra-red Spectrum:

The IR. spectrum in KBr of the antibiotic is shown in FIG. 3. The principal absorption bands are 812, about 860, 940, 985, 1092, 1215, 1340-1380, 1460, 1540, 1640, 2933, 2969, about 3370 cm.

The IR spectrum of a solution in chloroform shows the following absorption maxima: 865, 940, 990, 1045, 1077, 1095, 1360, 1460, 1520, 1658, 2880, 2940, 2973 and 3448 cm.

PMR Spectrum:

The PMR spectrum of MYC 8003 was taken in a mixture of hexadeutero-dimethylsulfonamide and CDC1 and measured at 60 Mo and is shown in FIG. 4. 8 values are indicated in ppm and tetramethylsilane was used as a reference.

Elementary Analysis:

Average values found are: C 63.8% H 7.6% N 3.5% O (by difference) 25.1%.

Molecular Weight:

The molecular weight determination was carried out by means of isothermic distillation. Two solutions, one of the antibiotic in acetone and the other of azobenzene (as reference) in acetone, were placed separately in a closed and evacuated system. Because of the difference in vapor tension above the solutions, the vapor moves until an equilibrium is reached when the solutions have equal molarities. The method was carried out at a constant temperature of 23C. The molecular weight calculated for the antibiotic was 7 14. A solution of the antibiotic in 50% aq.MeOH titrated by 0.1N NaOl-I gives a neutralization equivalent of 817. Microbiological Activity:

The microbiological activity of the antibiotic preparation towards a number of microorganisms has been determined by a micro liquid serial dilution test.

A stock solution of the test compounds at a concentration of 200,ug/ml in 0.05 molar phosphate buffer at a pH of 6.5 was prepared and serial 1:1 dilutions were made with a liquid medium inoculated with the test organism, using conventional glass spot-test plates. The plates were incubated 18 hours at 30C or 37C. The minimum inhibitory concentration (MIC) which is the smallest concentration of compound completely inhibiting the growth of the test organism is read and calculated in ,ug/ml. The results are given in Table 11.

TABLE 11 Minimum inhibitory Organism tested concentration ug/ml Bacillus suluillis ATCC 6633 50 Bacillus cereus ATCC 9139 0.3

Slapl i'lococcus aureus A 55 100 (ATCC 65388) Staphylococcus aureus A 321 100 Slapltvlococcus aureus A 335 100 Staphylococcus aureus L 16021) 200 Salmonella (Ill/Ill" P 43 Salmonella typhimurium R 127 100 Escherichia cnli U 20 100 Escherichia z'nli M 100 Escherichia coli NCT C 8196 Erwinia earolm'ora W 9 6 Minimum inhibitory concentration ug/ml Organism tested Pseudomonas aeruginosa L 94 Pseudunmnas aeruginosa 2396") 100 Proteus rettgeri A 821 100 Proteus mirabilis H 3 50 Proteus mirahilis' L 93 100 Proteus morganii 2241 100 Haemophilus influenzae A 773 2 Actinabacillus equuli T 3 1.5 Candida albicans A 7 100 Candida parapsilosis A 952 100 Tnrulopsis glabrata A 420 100 Saccharomyces cererisiae D 100 Trit'lwphytan mentagraphytes R 177 100 Aspergilus niger D 184 100 Laelobacillus acidophilus D 218 100 Closlridium weIc/tii A 738 10 Vibrio coli 1846 100 Streptococcus agalacliae A 732 0.9 Streptococcus disgalactiae A 730 0.6 Mycoplasma galliseplicum K 514 0.1 Mycoplasma synoriae A 2082 1 Mycoplasma suipneumoniae A 2174 l Mycoplasma h \'orhinus A 2230 3 wherein indicates penicillinase-producer; indicates recently isolated hospital strain.

The Table shows that the antibiotic possesses a high activity against Mycoplasma gallisepticum, but almost no activity against a number of human-pathogenic microorganisms. There is no activity again Mycoplasma gallisepticum in vivo.

Toxicity:

The toxicity of the antibiotic has been studied in various animals. The acute toxicity is very low; a dose of 1,000 mg/kg i.p. does not kill mice and oral administration to rats and chickens at concentrations up to 0.1% in the diet for three months does not result in any undesired pharmacological effect.

Application:

The new antibiotic of the invention has been found to be especially useful as a growth promoting agent for livestock, e.g. cattle, pigs and poultry. The growth promoting agent can be administered in the usual manner, for example, as an additive in animal food at a daily rate of 1 to 100 mg/kg, preferably 2.5 to 20 mg/kg.

The antibiotic may also have therapeutical value for diseases caused by certain intestinal microorganisms, such as Vibrio coli, Clostridium welchii.

Description of the microorganism:

The microorganism Streptomyces ramocissimus (CBS 190.69), which produces the antibiotic of the present invention is characterised by the following description, in which, for the determination, use has been made of Systematik der Streptomyceten by R. l-Iiitter 1957) and the International Journal of Systematic Bacteriology (1968), vol. 18 no. 2) with the rules for description prescribed by the International Streptomyces Project (hereinafter abbreviated to ISP).

A. The vegetative mycelium.

The growth on most growth media is good. The colonies possess the characteristic appearance of Actinomycetes and are formed as leather-like, somewhat plied colonies. Normally, the color of the colonies is not very characteristic as it varies from substantially colorless via light gray and light beige to light yellow, except on media on which the colonies are colored brown to dark brown by formation of melanine (malt peptone agar, brain-heart infusion agar).

B. The aerial mycelium.

On most media, an aerial mycelium is hardly or not visible macroscopically. On some media, such as yeast extract-malt extract agar, oat meal agar and, especially, inorganic salt-starch agar, however, aerial mycelium is formed in abundance. At first, such a mycelium is white, but it turns dark gray in good developments, and is built up from often rather short, irregularly branched hyphes having spore chains on short side axes in the form of simple loops or primitive coils having not more than two, three or four turns (section: Spira). Sometimes, two, three or four of those coils sprout as pseudo verticils from substantially the same spot on the main axes. Other spore chains sprout as primitive coils directly from the substrate mycelium (in a way similar to Retinaculum-Apertum). In addition, many sub-globose bodies are often visible in the aerial mycelium, probably due to an amount of spores from a primitive coil surrounded by a film of liquid.

C. The conidia.

In the spiral-like hyphes, strings of mostly over ten, somewhat elliptic conidia are formed. The surface of the conidia is smooth. The sizes are rather variable, but

the average sizes are about 0.9 to 1.3 u. D. Influence of temperature on growth.

The growth is slow at C., moderate at 26C., good between 30C. and 37C, and fairly good at 40C. Growth stops over 42C (mesophyl).

E. Physiological properties.

The physiological properties are shown in the following Table III.

TABLE III Property Diagnostic medium Physiological reactions Melanine formation H S formation Gelatin liquefaction Nitrate reduction Diastatie action Coagulation and Peptonisation of milk Melanine Medium according to Shinobu. I958 (ISP med. 7) "BactoPeptone Yeast Extract Iron agar" Triple Sugar Iron agar" from Difco Plain Gelatin Nitrate Reduction Medium according to Waksman Starch agar Litmus milk highly positive highly positive highly positive liquefield completely after -l6 days at 30C.

highly positive highly positive after 16 days coagulated and. for the greater part, peptonised (pH 7.9)

In Tables IV and V a survey is given of the growth and the appearance of the microorganism Streptomyces ramocissimus on a number of substrates.

Appearance of the microorganism after 16 days growth at 30C.

TABLE IV Substrate Vegetative mycelium mycelium Malt peptone agar Emersons agar Nutrient agar Nutrient agar 17: soluble starch Oat meal agar chocolate brown colored colonies light brown to beige colonies light brown yellow to yellow beige colonies light brown yel low to yellow beige colonies light beige to yellow beige contmued Soluble Aerial Vegetative Substrate Growth pigmycelium mycelium ment white. later on light y Starch agar good light none light yellow to yellow gray Potato-glucose good dirty none rather deeply agar dark plied. dark brown brown colonies Czapek-glucose fairly none none light yellow to agar good gray Czapek-saccharose fairly none none light grayish agar good white Czapek-glycerol fairly none none light gray agar good Glucose asparagood none none light yellow, gine agar merging colonies Glycerol asparagood none very weak light gine agar scarce greenish gray at the edge of the colonies Glucose calcium 'good none none very light yelmalate agar low to white Sodium citrate modernone none graybeige agar ate Brain-heart moderblack none chocolate brown infusion agar ate brown KusterWilliams good light very very light agar (viz. Nature brown scarce. greenish 202 1964 p. 928) graybeige white Bennett's agar good light very light brown to brown scarce. beige white Potato slices good almost none black brown,

black highly plied colonies TABLE V Themicroorganism after 13 days growth on media prescribed by ISP.

Soluble Aerial Vegetative Substrate Growth pigmycelium mycelium ment Yeast malt ex good none rather light brown to tract agar abundant. beige (ISP II) white.

later on light gray Oat meal agar good none very flat. very (ISP II) scarce. light yellow chiefly to gray coloalong the nies having edges edges growing very deep in the agar Inorganic saltsgood none abundant. flat. light starch agar light gray. gray to very (ISP lV) later on light yellow almost beige colonies black Glycerol good none rather light gray to asparagine abundant. light yellow agar ([5? V) light gray, gray colonies later dark gray to almost black B. at 37C.

lSP Il good none rather colonies having abundant. edges growing light gray rather deep in the agar ISP III good none rather flat. very abundant, light gray to A comparison of the properties and characteristics of Streptomyces ramocissimus CBS 190.69 with those of related strains of Streptomyces, such as Streptomyces tendae CBS 432.59, Streptomyces tendae CBS 565.68 and Streptomyces collinus lst 301 (ETH 24.318), when grown on media recommended by ISP at 30 and 37C., makes it apparent that Streptomyces ramocissimus is different from those previously known strains of Streptomyces.

The aerial mycelium of Streptomyces collinus, under suitable circumstances, may grow to markedly long, little branched hyphes lying more or less horizontally over the colony, along which short, generally loopformed spore-chains are implanted. This is in great contrast to the aerial mycelium of Streptomyces ramocissimus which is markedly short and highly irregularly branched. The colors of the two mycelia are also quite different. The aerial mycelium of Streptomyces ramocissimus is gray to dark gray, whereas that of Streptomyces collinus is generally white, light yellow or creamcolored to only light gray-colored, and the substrate mycelium, especially when grown on Basal mineral salts agar media to which different carbon compounds have been added, is predominantly grayish for Streptomyces ramocissimus whereas that of Streptomyces collinus is light brown, brown red or even egg-yellow. Differences occur also in the physiological properties in nitrate-reduction, gelatin-liquefaction, the amount of starch hydrolysis and the decomposition of calcium oxalate and oxalic acid. These differences indicate that the microorganism cannot be arranged under Streptomyces collinus.

The differences between Streptomyces ramocissimus and the two above mentioned Streptomyces tendae are less than between Streptomyces ramocissimus and Streptomyces collinus. For example, the color of the aerial mycelium of Streptomyces ramocz'ssimus shows only a small difference with that of Streptomyces tendae, while the spore-chains are often bent into hooks or loops. The spore-chains of the examined Streptomyces tenaae, however, are generally longer than those of Streptomyces ramocissimus. The spore-chains of Streptomyces tena'ae generally rise up directly from the agar, whereas, although sometimes observed at the sporechains of Streptomyces ramocissimus, too, the sporechains of this strain are generally arranged as monopodial side-branches along short aerial hyphes. A more important taxonomical different resides in the formation of a melanoidal pigment on the I.S.P. media 6 and 7 (the melanine medium according to Shinobu and the Peptone yeast extract agar, respectively). The examined Srreptomyces tendae strains do not form a brown pigment on those media, whereas Streptomyces ramocissimus is pronouncedly melanine-positive. Other differences in physiological properties were observed in the following properties:

degree of starch hydrolysis decomposure of calcium oxalate and oxalic acid highly positive weakly positive negative positive Based on the above mentioned differences, it is apparentthat Streptomyces ramocissimus does not belong to Streptomyces tendae.

Production of the antibiotic MYC 8003.

According to a feature of the present invention, the new antibiotic is prepared by the process which comprises aerobically cultivating the microorganism Streptomyces ramocissimus (CBS 190.69), or antibiotic-producing mutant thereof, in an aqueous nutrient medium containing assimilable sources of carbon, nitrogen and inorganic substances at a temperature between about 20 and about 40C, preferably between about 28 and 40C and a pH between about 5 and 9, preferably between about 6.5 and about 8, and separating the antibiotic formed during the cultivation. Fermentation of the microorganism may be carried out with the liquid media containing the usual carbon, nitrogen, phosphorus calcium, iron, sulfur, magnesium, potassium, vitamin and trace-element sources, such as media containing molasses, malt paste, peanut flour, lactose, potato starch, corn steep, and yeast extract.

The separation of the antibiotic from the culture medium can be carried out in several ways. For example, the culture filtrate may be extracted with an organic solvent for the antibiotic such as butanol, chloroform or, preferably, methyl isobutyl ketone whereby the'antibiotic is collected in the organic phase. Another method of recovery consists in extraction of the culture as such or at an adjusted pH value (whole broth extraction) with a suitable organic solvent (chloroform, methyl isobutyl ketone, butyl acetate, etc.) Still another method consists in adding a large volume (e.g. 0.5 to 5 times the culture volume) of an organic solvent such as an alcohol or ketone to the culture broth, followed by filtration or centrifugation. From the organic phase the antibiotic may be precipitated by concentration or addition of a poor solvent for the antibiotic such as petroleum ether. The pH for an optimal extraction is about 5 to 8. Purification of the antibiotic may be carried out by chromatography on an A1 0 column, partition chromatography, and/or countercurrent distribution, using methyl isobutyl ketone, ethyl acetate or a 1:1 mixture of ethyl acetate and diethyl ether as the mobile phase, and buffers of bicarbonate, phosphate or borate as the immobile phase.

For practical use as a feed additive for live-stock, the product isolated from the culture medium by extraction and precipitation may be used without further purification.

In the following examples there are described several preferred embodiments to illustrate the invention.

9 However, it should be understood that the invention is not intended to be limited to the specific embodiments.

EXAMPLE I.

and emulsions formed were broken with Hyflo Supercel filter aid. The organic liquids were mixed and concentrated to about 1 liter by evaporation under reduced pressure and evaporation with a rotary evaporator. The concentrate formed was slowly added to 5 liters of petroleum ether (boiling range of 40C to 60C.) and the precipitate formed was filtered off with a glass filter (D 3), washed with fresh petroleum ether and dried to obtain a yield of 78 g. of a yellow colored powder.

Using partition chromatography, 2 g. of the crude antibiotic (in the acid form) was purified. The stationary phase used consisted of Hyflo impregnated with a 0.1 molar Na CO /NaI-ICO buffer at pH 11, and the mobile phase consisted of a mixture of petroleum ether and butyl acetate. A yield of 0.828 g. of the purified anitbiotic having the physico-chemical properties hereinbefore described was obtained.

A certain amount of the antibiotic was dissolved in water with addition of 0.1 N sodium hydroxide to pH 9 until a saturated solution was obtained. The solution was filtered and evaporated azeotropically with addition of butanol, and the butanolic residue was collected in a small amount of anhydrous butanol (in vacuo at about 45C. To the stirred solution, petroleum ether was added dropwise until all the salt was precipitated. The precipitate was filtered off, washed and dried to give the sodium salt of the antibiotic.

According to another feature of the invention there are provided animal feedstuffs, more especially in a form for use in feeding cattle, pigs and poultry, supplemented by a significant proportion of the antibiotic or a non-toxic, pharmaceutically acceptable salt, e.g. sodium salt, thereof. The antibiotic or salt thereof may also be dispersed in, or mixed with, any suitable inert physiologically innocuous carrier or diluent, which is orally administrable to an animal, nonreactive with the antibiotic and not harmful to the animals on oral administration. The antibiotic or said salt thereof may be conveniently incorporated in the feedstuff, carrier or diluent by conventional methods such as milling, stirring, or tumbling. Concentrates and supplements including the antibiotic, which may be mixed with other components of animal feedstuff, are also within the invention. Generally the amount of antibiotic or salt thereof included in an animal feedstuff to give a satisfactory growth-promoting effect is about 1 ppm. to 50 ppm. by weight of the feedstuff. The following Examples illustrate the growth promoting effect of the antibiotic.

EXAMPLE II Slaughter chickens are given the antibiotic, in the form of the sodium salt obtained in Example I, in a mixture with a component of the feed (wheat flour),

10 the amount of antibiotic in the feed (based on the weight of the feed) being as specified in the following Table, which gives the weight of the chickens after 3, 5 and 7 weeks.

TABLE VI Age 3 weeks 5 weeks 7 weeks increase 7: increase 7: increase Control (Oppm) 100 100 5 ppm 104 103 103 10 ppm 107 104 20 ppm 109 107 105 The table shows that an increase in growth of the chickens is obtained upon administration of the antibiotic and an improvement of feed conversion of 3 to 5% is reached for the chickens in 7 weeks when the feed contains 1-50 ppm of antibiotic.

EXAMPLE III TABLE VII antibiotic 6 weeks 12 weeks feed feed growth conversion grown conversion 0 ppm 100 100 100 100 (control) 5 ppm 107 95 104.5 98 10 ppm 108.5 92.5 104 99 The Table shows a growth promoting effect of the antibiotic according to the invention.

Various modifications of the composition and methods of the invention may be made without departing from the spirit or scope thereof and it is to be understood that the invention is to be limited only as defined in the appended claims.

We claim:

1. A member of the group consisting of the antibiotic MYC 8003, which is a yellow, salt-forming weak acid solid having the analysis: carbon, 63.8%; hydrogen, 7.6%; nitrogen, 3.5%; and oxygen, 25.1%; consisting of equilibrium-forming components, with an optical rotation [(11 of 60 (1% methanolic solution), poorly soluble in carbon tetrachloride and benzene, soluble in chloroform, methyl isobutyl ketone, butyl acetate, ethyl acetate, methanol and alkaline solutions, insoluble in diethyl ether, petroleum ether, water and acid solutions, showing a slightly positive reaction in the aromate test, forming a red color with concentrated sulfuric acid, a dark brown color in the Pauly reaction, a dark red color and turbidity with ferric chloride, and precipitation with bromine water, showing gas production at C, showing further gas production at about 152C and showing a decomposition at 164l74C.

showing in the ultraviolet region of the spectrum ab-.

sorption maxima at 233, 276, 286, and 327 nm as in FIG. 1, and in the infrared region, in KBr, absorption bands at 812. about 860, 940, 985, 1092, 1215, 1340l380, 1460. 1540, 1640, 2933', 2969 and about 3370 cm as in FIG. 3 and an Rf-value of 0.10 of the 12 microorganism Streptomyces ramocissimus (CBS 190.69) in an aqueous nutrient medium containing assimilable sources of carbon, nitrogen and inorganic substances until substantial antibiotic activity is imparted to said medium by antibiotic MYC 8003 and recovering the antibiotic formed during the cultivation. =l =l= 

1. A MEMBER OF THE GROUP CONSISTING OF THE ANTIBIOTIC MYC 8003, WHICH IS A YELLOW, SALT-FORMING WEAK ACID SOLID HAVING THE ANALYSIS: CARBON, 63.8%; HYDROGEN, 7.6%; NITROGEN, 3.5% AND OXYGEN, 25.1%; CONSISTING OF EQUILIBRIUM-FORMING COMPONENTS, WITH AN OPTICAL ROTATION (A)D22 OF -60* (1% METHANOLIC SOLUTION), POORLY SOLUBLE IN CARBON TETRACHLORIDE AND BENZENE, SOLUBLE IN CHLOROFORM, METHYL ISOBUTYL KETONE, BUTYL ACETATE, ETHYL ACETATE, METHANOL AND ALKALINE SOLUTIONS, INSOLUBLE IN DIETHYL ETHER, PETROLEUM ETHER, WATER AND ACID SOLUTIONS, SHOWING A SLIGHTLY POSITIVE REACTION IN THE AROMATE TEST, FORMING A RED COLOR WITH CONCENTRATED SULFURIC ACID, A DARK BROWN COLOR IN THE PAULY REACTION, A DARK RED COLOR AND TURBIDITY WITH FERRIC CHLORIDE, AND PRECIPITATION WITH BROMINE WATER, SHOWING GAS PRODUCTION AT 135*C, SHOWING FURTHER GAS PRODUCTION AT ABOUT 152*C AND SHOWING A DECOMPOSITION AT 164*-174*C, SHOWING IN THE ULTRAVIOLET REGION OF THE SPECTRUM ABSORPTION MAXIMA AT 233, 276, 286, AND 327 NM AS IN FIG. 1, AND IN THE INFRARED REGION, IN KBR, ABSORPTION BANDS AT 812, ABOUT 860, 940, 985, 1092, 1215, 1340-1380, 1460, 1540, 1640, 2933, 2969 AND ABOUT 3370 CM-1 AS IN FIG. 3 AND AN RF-VALUE OF 0.10 OF THE CHIEF COMPONENT, WHEN CHROMATOGRAPHED WITH A MIXTURE OF BENZENE, ETHANOL AND 33% AMMONIA IN THE RATIO OF 65:40:9 AND HAVING THE PMR SPECTRUM OF FIG. 4, AND ITS NON-TOXIC, PHARMACEUTICALLY ACCEPTABLE SALTS.
 2. The antibiotic of claim 1 in the form of its sodium salt.
 3. A process for the production of the antibiotic MYC 8003 of claim 1 which comprises cultivating the microorganism Streptomyces ramocissimus (CBS 190.69) in an aqueous nutrient medium containing assimilable sources of carbon, nitrogen and inorganic substances until substantial antibiotic activity is imparted to said medium by antibiotic MYC 8003 and recovering the antibiotic formed during the cultivation. 